Steam slide-valve



. 4 Sheets-Sheet 1. B. F. STURTEVANT.

STEAM SLIDE VAL -(No Model.

VB Patented May 9, 1882 'Y Y WITNESSES (No Model.) v 4 Sheets-Sheet 2 B. F. STURTEVANT.

STEAM SLIDE VALVE.

No.- 257,530. Patented May 9,1882.

WIIT-IIVESSIES No Model.) x 4 SheetSSheet a. B. F. STURTE'VANT.

STEAM SLIDE VALVE. No. 257,530. PatentedMay 9,1882

WITNESSES WV-EH70 mam/mm (No Model.) 4 Sheets-Sheet 4.

B. P. STURTBVANT. STEAM SLIDE VALVE.

No. 257,530. Patented May 9,1882.

A fforney Ilwrrnn STATES PATENT Genres.

BENJAMIN F. STURTEVANT, OF BOSTON, MASSACHUSETTS.

STEAM SLIDE-VALVE.

SPECIFICATION forming part of Letters Patent No. 257,530, dated May 9, 1882.

Application filed February 25, 1S82. (No model.)

To all whom it may concern:

Be it known that I, BENJAMIN F. STURTE- VANT, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Steam Slide- Valves; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it pertains to make and use the same.

My invention relates to an improvement in steam slide-valves, the object being to provide a single valve capable of producing the following functions, to. wit: to open a series of independent steam-admission ports at one end of the valve and an exhaust-steam passage at the opposite end thereof, to out off the admission of steam to the cylinder at the desired portion of the stroke of the piston, and also to cut off the exhaust at the proper time to insure a steam-cushion at each end of the cylinder.

ith these ends in view, my invention consists in a valve embodying certain features of construction and arrangement of parts, as will hereinafter be described, and pointed out in the claims.

In the accompanying drawings, Figure 1 is a longitudinal section of a valve constructed in accordance with my invention, the valve being represented at the center of the stroke. Fig. 2 is a similar view, showing the valve at one-end of its stroke. Fig.3 is a plan View of the valve. Fig. 4 is a transverse section, and

Fig. 5 is a modification.

A represents the valve-chest. B is the steaminlet. 0 O are the main steam-ports leading to the opposite ends of the steam-cylinder, and l) D are supplemental steam -ports leading from the face of the valve seat to the main steam-ports, and communicating therewith. The valve-seat is constructed with the faces a a, b b, and c 0.

Above the valve-seat is located a cap or cover,E, provided at opposite ends with the steampassages F F, which are wide at their outer ends, as represented atf, and narrow at their inner ends, as at f. The cap E is constructed with the working-faces a a 1) b and c c.

The cover E is set in the following manner: Through the top of the valve chest are inserted four set-screws, P, one at each corner of the cover. These set-screws are hollow and receive the studs Q, which are rigidly secured to thecovcr, and which extend up through the set-screw and a cap, 1%, placed over the same, and receive a nut, S, on their upper ends. The set-screws P are first turned down so as to bear on the cover. The caps R are then applied, and the nuts S then screwed down to lift the cover snuglyagainst the lower ends of the set-screws.

WhileI have represented the meansdescribed for adjusting the cover, I do not restrict myself to these particular devices for this purpose, as I may resort to other devices for producing the same result.

The valve G is provided with a central bore, H,in which is secured the valve-rod. The center of the valve is furnished with the main steam-admission port I, which communicates with steam-chambers i '17, formed in the opposite ends of the valve. At the outer ends of these steam chambers are two ports, 9 g, the ports g opening from the steam-chambers it to the under side or face of the valve and the ports 9 to the upper face of the valve.

Near each end of the valve is formed a steampassage, 7b, which extends through the valve, and is considerably wider than the ports 9.

In Fig. 1 the valve is on its center,with both the admission and exhaust ports closed. Fig. 2 represents the valve shifted to its full stroke. In this position steam flows from the main inlet B, through the port I, through the branch port D to the end of the cylinder, through the main port (3. Stcamalso flows from port I through the passageF in the cap E, and through the steam-passage h of the valve to the port 0. Again,when the valve is in this position the chamber 15, communicating with the port I, is filled with steam,\vhich escapes. through the port g direct to the port 0, and also through the port g and down through the steanrpassage h. Thus it will be observed that by a slight movement of the valve four separate steam-ports are opened to allow of the free supply of steam to the main port or passage O,leading to the end of the cylinder.

Referring now to the opposite end of the valve,it will be found that both ports 0 D are closed to the steam-ports of the valve, the end of which has uncovered the port 0 to afford a free exhaust from the opposite end of the cylinder. The valve is constructed so as to cut off the admission of steam to the cylinder at.

the desired portion of the stroke of the piston, and also to cut off the exhaust at the proper time to insure a steam-cushion at each end of the cylinder.

Provision for cutting off the admission and exhaust is made in the original construction of the valve, so that when it is once set it will be impossible for it to become displaced, as it is a single solid structure, and of course must operate at all times alike. In Fig. 5 I have represented a valve having four outlet-ports com municating with the steam-chamber in each end of the valve. This valve is constructed the same as the one heretofore described, except that it is provided with two extra outletports,jj, and anothersnpplemental steam-port,

J, through which the steam is conveyed to the main port leading to the end of the cylinder. Thus by this plan of valve I am enabled to secure any desired number of steam-admission ports in the valve and uncover them simultaneously, so as to insure a free delivery of steam to the cylinder.

It is obvious that the operation of this valve may be reversed and the steam taken in at the ends of the valve and exhausted through the central port. Further, that the valve may be constructed of cylindrical form instead of fiat, as represented.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. A valve constructed with a series of ad mission-ports which communicate with the cylinder-ports at each end, and adapted to have its ends open and close the exhaust-ports at each stroke, substantially as set forth.

2. A valve having a steam-chamber in each end and provided with a series of admissionports which communicate with the cylinderports at each end, and adapted to have its ends open and close its exhaust-ports at each stroke, substantially as set forth.

3. The combination, with the cylinder-ports and the valve cap or cover, of a double-faced valve provided with steam-chambers and with a series of ad mission-ports which communicate with the cylinder-ports, the ends of the valve being constructed and arranged to open and close the exhaust at each stroke, substantially as set forth.

4. The combination, with the main and supplemental ports for supplying steam to the ends of the cylinder, of a valve provided with a port adapted to open a supplemental port at each stroke, and with two or more independent ports at each end for supplying steam to the cylinder, substantially as set forth.

5. The combination, with the cylinder-ports and valve cap or cover, of a valve provided with a series of ports at each end, and with a steam-passage to allow the steam to flow from a port in the valve through a passage in the cap and down through the valve to the cylinder-port, substantially as set forth.

In testimony whcreofI have signed this specification in the presence of two subscribing witnesses.

BENJ. F. STURTEVANT. Witnesses:

W. H. ALLEN, ELMER P. HOWE. 

